Generally recognized as safe (GRAS) is an American Food and Drug Administration (FDA) designation that a chemical or substance added to food is considered safe by experts, and so is exempted from the usual Federal Food, Drug, and Cosmetic Act (FFDCA) food additive tolerance requirements.  The concept of food additives being "generally recognized as safe" was first described in the Food Additives Amendment of 1958, and all additives introduced after this time had to be evaluated by new standards.
On January 1, 1958, the FDA established the Food Additives Amendment of 1958, with a list of 700 food substances that were exempt from the then new requirement that manufacturers test food additives before putting them on the market.  On August 31, 1960, William W. Goodrich, assistant general counsel of the FDA, addressed the annual meeting (16 Bus. Law. 107 -1960-1961) of the FFDCA. The purpose of the meeting was the forthcoming March 6, 1961, effective date of the enforcement provisions of the "Food Additives Amendment of 1958", referred to as GRAS. 
A GRAS determination can be self-affirmed or the FDA can be notified of a determination of GRAS by qualified non-governmental experts:
- Self-affirmed. The manufacturer of this chemical or substance had performed all necessary research, including the formation of an expert panel to review safety concerns, and is prepared to use these findings to defend its product's GRAS status.
- FDA Response to GRAS notification.  The manufacturer has performed all the aforementioned due diligence, and submitted a GRAS notification to inform the Food & Drug Administration of a determination that the use of a substance is GRAS. Following evaluation the FDA provides three possible responses: 1. FDA does not question the basis for the notifier's GRAS determination,  2. the notification does not provide a sufficient basis for GRAS determination, or 3. the FDA has, at the notifier's request, ceased to evaluate the GRAS notice.
As of June 2015 [update] (beginning in 1998), 572 ingredient or food substances have been filed with the FDA.  These petitions, submitted by sponsors or manufacturers, are reviewed for the safety evidence contained in the document. FDA posts status of the review as either without further questions or the petition is withdrawn by the applicant. 
For substances used in food prior to January 1, 1958, a grandfather clause allows experience based on common use in food to be used in asserting they are safe under the conditions of their intended use.
The Code of Federal Regulations, Revised as of April 1, 2010 [update],  includes (CFR) title 21 170.30(b) that provides general recognition of safety through scientific procedures requires the same quantity and quality of scientific evidence as is required to obtain approval of the substance as a food additive  and ordinarily is based upon published studies, which may be corroborated by unpublished studies and other data and information.
The substance must be shown to be "generally recognized" as safe under the conditions of its intended use. The proponent of the exemption has the burden of proving that the use of the substance is "generally recognized" as safe.  To establish such recognition, the proponent must show that there is a consensus of expert opinion regarding the safety of the use of the substance. The existence of a severe conflict among experts regarding the safety of a substance precludes a finding of general recognition.
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When a use of a substance does not qualify for the GRAS exemption, that use of the substance is subject to the premarket approval mandated by the Federal Food, Drug, and Cosmetic Act. In such circumstances, the FDA can take enforcement action to stop distribution of the food substance and foods containing it on the grounds that such foods are or contain an unlawful food additive. 
- Food and Drug Administration
- Generally recognized as safe and effective
- Life Sciences Research Office
- Novel food
- Substantial equivalence
- "Generally Recognized as Safe (GRAS)". Fda.gov. Retrieved 2013-03-17.
- "GRAS history". diet.com. Retrieved 2010-11-27.
- "Address to the FFDCA concerning GRAS". heinonline.org. Retrieved 2010-11-27.
- "GRAS Notices, US Food and Drug Administration". FDA. June 2015. Retrieved 3 June 2015.
- "CRF revised statutes". accessdata.fda.gov. Retrieved 2010-11-27.
- "Summary Table of Recommended Toxicological Testing for Additives Used in Food". Fda.gov. 2009-05-18. Retrieved 2009-09-06. - broken link
- "Federal Register Proposed Rules - 62 FR 18937 April 17, 1997 - Substances Generally Recognized as Safe". cfsan.fda.gov. Archived from the original on September 16, 2008.
- U.S. Food and Drug Administration. (1993). Everything Added to Food in the United States. Boca Raton, Florida: C.K. Smoley (c/o CRC Press, Inc.).